Update TaskSync Protocol from V4 to V5.2

Since the latest version of TaskSync is [5.2](https://github.com/4regab/TaskSync/pull/19), should we update [instructions/tasksync.instructions.md](https://github.com/github/awesome-copilot/blob/main/instructions/tasksync.instructions.md) which is currently [based on TaskSync version 4](https://github.com/github/awesome-copilot/pull/174/changes)?

cc: @4regab